The value of the accelerated approval pathway: real-world outcomes associated with reducing the time between innovations.

Aim: We investigated the effect of shortening time between innovations with the accelerated approval (AA) pathway on patient outcomes for three solid tumors. Methods: This real-world analysis evaluated patients receiving sequential AA pathway-approved innovations after initial treatment with existing therapies in three solid tumor case studies. Outcomes attributable to AA were estimated and assumed approval occurred at the time of conversion to approval and extrapolated to the US population. Results: Survival gains from accessing innovative therapies were 2.3-3.8-times higher when using the AA pathway. At the US population level, AA was associated with ∼8000 life-years gained across all three tumor case studies. Conclusion: In areas of rapid clinical development, the value of existing therapies can be enhanced by earlier access to AA pathway innovations and should be considered when evaluating the AA program.

What is this study about? The US Food and Drug Administration's accelerated approval pathway provides patients with access to innovative drugs sooner than standard regulatory pathways. Using three case studies in solid tumors, this study measured how many patients on current cancer drugs received future cancer drugs because of the accelerated approval pathway and asked whether quicker access to new drugs resulted in them living longer.What were the results? In three cancer case studies, the accelerated approval pathway led to more patients receiving future cancer drugs. Patients who received future drugs through the AA pathway lived longer than patients who did not have access to them.What do the results of the study mean? The accelerated approval pathway is important because it can improve outcomes of current cancer drugs by giving patients additional treatments to choose from in the future and therefore a chance to live longer. Policymakers should consider this when thinking about making changes to the accelerated approval pathway.

An Adult With Undifferentiated Embryonal Sarcoma of the Liver: A Case Report of a Rare Encounter.

Undifferentiated embryonal sarcoma of the liver (UESL) is a rare, aggressive tumor mainly found in children but can also appear in adults. Its diagnosis in adults remains a conundrum; it is often identified late due to its non-specific symptoms and resemblance to benign lesions. A comprehensive treatment regimen involving surgical intervention, chemotherapy, and possibly radiation significantly boosts survival rates. Imaging often yields inconclusive outcomes, further complicating the diagnostic process. Here, we report the case of a 28-year-old female diagnosed with UESL, emphasizing the need for timely intervention. Undifferentiated embryonal sarcoma of the liver requires differentiation from a variety of hepatic tumors in adults. Though there are no distinctive characteristics to differentiate UESL from other hepatic masses, its morphology and immunohistochemical profiles significantly vary. The staging often reveals UESL as a large, well-defined mass with the potential for diverse differentiation. Its prognosis has been considerably improved with the advent of multidisciplinary treatment. Surgical resection remains a cornerstone, often combined with chemotherapy. While pediatric cases exhibit better overall survival rates than adults, outcomes heavily depend on the chosen treatment regimen. A combination of chemotherapy and complete tumor removal has been found to significantly elevate survival chances. Disease recurrence remains a challenge and is influenced by treatment strategy. In conclusion, the diagnosis and treatment of UESL are fraught with challenges, particularly in adults. A multidimensional approach, combining various therapies, is paramount for better outcomes. Continuous research and enhanced awareness are crucial for improving diagnostic precision and treatment outcomes for UESL patients.

Unpacking the Racial Gap: Helicobacter pylori Infection Clearance Among Different Racial Groups.

Introduction Helicobacter pylori (H. pylori) is a bacteria causing chronic stomach infections, influenced by various factors, including host traits and bacterial virulence. It uses both urease-dependent and independent mechanisms to survive acidic gastric environments. Management entails diagnosis, treatment, and eradication verification. Combining drugs is key to overcoming resistance and ensuring bacteria elimination, thus preventing recurrence and complications. H. Pylori eradication mitigates gastric cancer risk and alleviates symptoms. Racial disparities persist despite declining H. pylori and gastric cancer incidence in the United States (US). African Americans (AA) have higher gastric cancer risks than non-Hispanic Whites. Addressing these disparities is crucial to protect high-risk populations. Methods This study retrospectively compiled H. pylori infection data from 2009 to 2022, categorized by race. Propensity score matching balanced initial group characteristics before analysis. Chi-squared and odds ratio tests were used on the cohort, with Kaplan Meier and Log Rank methods evaluating disease clearance in ethnic groups. Data were extracted from the Sunrise Electronic Medical Record software, including patient demographics, health details, and treatment specifics. Patients aged 18-65 with H. pylori infection at Nassau University Medical Center, who followed their treatment, were selected. Data were processed using Statistical Package for the Social Sciences (SPSS) and RStudio software. Results The study initially included 10,040 H. pylori-diagnosed patients, with 9,288 meeting the study's criteria after attrition. Predominantly female (64.7%), the cohort was racially diverse. A longer disease clearance time was noted among Hispanics (p=0.044). Binomial logistic regression analysis identified influential factors like high school graduation rates, poverty level income, and language proficiency on disease clearance. An odds ratio analysis further emphasized language barriers (HR 0.346, p=0.043) and education status (HR 0.756, p=0.025) as primary covariates impacting disease clearance, underlining the role of socio-economic factors and language proficiency in health outcomes. Conclusion The study highlights racial disparities in H. pylori clearance rates, particularly among Hispanics, necessitating culturally sensitive interventions. It advocates for improved diagnostics, increased healthcare access, and social determinants of health-focused initiatives. It identifies socio-economic status and language proficiency as key factors impacting health outcomes, calling for actions to bridge these disparities. Addressing these differences can decrease healthcare inequalities and economic burden, improving overall health outcomes and reducing costs associated with H. pylori clearance.

Is gastroschisis associated with county-level socio-environmental quality during pregnancy?

BACKGROUND: Gastroschisis prevalence more than doubled between 1995 and 2012. While there are individual-level risk factors (e.g., young maternal age, low body mass index), the impact of environmental exposures is not well understood. METHODS: We used the U.S. Environmental Protection Agency's Environmental Quality Index (EQI) as a county-level estimate of cumulative environmental exposures for five domains (air, water, land, sociodemographic, and built) and overall from 2006 to 2010. Adjusted odds ratios (aOR) and 95% confidence interval (CI) were estimated from logistic regression models between EQI tertiles (better environmental quality (reference); mid; poorer) and gastroschisis in the National Birth Defects Prevention Study from births delivered between 2006 and 2011. Our analysis included 594 cases with gastroschisis and 4105 infants without a birth defect (controls). RESULTS: Overall EQI was modestly associated with gastroschisis (aOR [95% CI]: 1.29 [0.98, 1.71]) for maternal residence in counties with poorer environmental quality, compared to the reference (better environmental quality). Within domain-specific indices, only the sociodemographic domain (aOR: 1.51 [0.99, 2.29]) was modestly associated with gastroschisis, when comparing poorer to better environmental quality. CONCLUSIONS: Future work could elucidate pathway(s) by which components of the sociodemographic domain or possibly related psychosocial factors like chronic stress potentially contribute to risk of gastroschisis.

The Path to Sustainable Healthcare: Implementing Care Transition Teams to Mitigate Hospital Readmissions and Improve Patient Outcomes.

Introduction Hospital readmissions within 30 days suggest care quality issues and increased mortality risks. They result from ineffective initial treatment, poor discharge planning, and inadequate post-acute care. These high readmission rates harm patient outcomes and financially strain healthcare institutions, inviting penalties and discouraging potential patients. Enhancing inpatient care, care transitions, and case management is crucial to lowering readmissions. Our research underscores the role of care transition teams in reducing readmissions and financial stress in hospitals. By consistently applying transition strategies and focusing on high-quality care, we can improve patient outcomes and ensure hospital success in the long run. Methods This two-phase study investigated readmission rates and risk factors in a community hospital from May 2017 to November 2022. Phase 1 determined a baseline readmission rate and identified individual risk factors using logistic regression. In phase 2, a care transition team addressed these factors by providing post-discharge patient support through phone calls and assessing social determinants of health (SDOH). Readmission data from the intervention period was compared to baseline data using statistical tests. Data, including demographics, medical conditions, and comorbidities, were collected via electronic medical records and the International Classification of Diseases (ICD-10 codes). The study focused on patients aged 20-80 with readmissions within 30 days. Exclusions were made to minimize confounding effects from unmeasured comorbidities and ensure an accurate representation of factors affecting readmissions. Results In the study's initial phase, 74,153 patients participated, with an 18% mean readmission rate. Women accounted for 46% of readmissions, and the white population had the highest rate (49%). The 40-59 age group showed a higher readmission rate than other age groups, and certain health factors were identified as risk factors for 30-day readmission. In the subsequent phase, a care transition team intervened with high-risk groups using an SDOH questionnaire. They contacted 432 patients, resulting in a reduced overall readmission rate of 9%. The 60-79 age group and the Hispanic population experienced higher readmission rates, and the previously identified health factors remained significant risk factors. Conclusion This study emphasizes the crucial role of care transition teams in reducing hospital readmission rates and easing the financial strain on healthcare institutions. By identifying and addressing individual risk factors, the care transition team effectively lowered the overall readmission rate from 18% to 9%. Continually implementing transition strategies and prioritizing high-quality care focused on minimizing readmissions are essential for improving patient outcomes and long-term hospital success. Healthcare providers should consider utilizing care transition teams and social determinants of health assessments to better understand and manage risk factors and tailor post-discharge support for patients at higher risk of readmission.

Gene-Level Germline Contributions to Clinical Risk of Recurrence Scores in Black and White Patients with Breast Cancer.

Continuous risk of recurrence scores (CRS) based on tumor gene expression are vital prognostic tools for breast cancer. Studies have shown that Black women (BW) have higher CRS than White women (WW). Although systemic injustices contribute substantially to breast cancer disparities, evidence of biological and germline contributions is emerging. In this study, we investigated germline genetic associations with CRS and CRS disparity using approaches modeled after transcriptome-wide association studies (TWAS). In the Carolina Breast Cancer Study, using race-specific predictive models of tumor expression from germline genetics, we performed race-stratified (N = 1,043 WW, 1,083 BW) linear regressions of three CRS (ROR-S: PAM50 subtype score; proliferation score; ROR-P: ROR-S plus proliferation score) on imputed tumor genetically regulated tumor expression (GReX). Bayesian multivariate regression and adaptive shrinkage tested GReX-prioritized genes for associations with tumor PAM50 expression and subtype to elucidate patterns of germline regulation underlying GReX-CRS associations. At FDR-adjusted P < 0.10, 7 and 1 GReX prioritized genes among WW and BW, respectively. Among WW, CRS were positively associated with MCM10, FAM64A, CCNB2, and MMP1 GReX and negatively associated with VAV3, PCSK6, and GNG11 GReX. Among BW, higher MMP1 GReX predicted lower proliferation score and ROR-P. GReX-prioritized gene and PAM50 tumor expression associations highlighted potential mechanisms for GReX-prioritized gene to CRS associations. Among patients with breast cancer, differential germline associations with CRS were found by race, underscoring the need for larger, diverse datasets in molecular studies of breast cancer. These findings also suggest possible germline trans-regulation of PAM50 tumor expression, with potential implications for CRS interpretation in clinical settings. SIGNIFICANCE: This study identifies race-specific genetic associations with breast cancer risk of recurrence scores and suggests mediation of these associations by PAM50 subtype and expression, with implications for clinical interpretation of these scores.

Urinary polycyclic aromatic hydrocarbon metabolites and mortality in the United States: A prospective analysis.

BACKGROUND: Polycyclic aromatic hydrocarbons (PAHs) are ubiquitous organic compounds associated with chronic disease in epidemiologic studies, though the contribution of PAH exposure on fatal outcomes in the U.S. is largely unknown. OBJECTIVES: We investigated urinary hydroxylated PAH metabolites (OH-PAHs) with all-cause and cause-specific mortality in a representative sample of the U.S. population. METHODS: Study participants were ≥20 years old from the National Health and Nutrition Examination Survey 2001-2014. Concentrations (nmol/L) of eight OH-PAHs from four parent PAHs (naphthalene, fluorene, phenanthrene, pyrene) were measured in spot urine samples at examination. We identified all-cause, cancer-specific, and cardiovascular-specific deaths through 2015 using the National Death Index. We used Cox proportional hazards regression to estimate adjusted hazard ratios (HRs) and 95% confidence intervals (CIs) for the association between ΣOH-PAHs and mortality endpoints. We assessed potential heterogeneity by age, gender, smoking status, poverty, and race/ethnicity. Additionally, we examined the overall mixture effect using quantile g-computation. RESULTS: In 9,739 eligible participants, there were 934 all-cause deaths, 159 cancer-specific deaths, and 108 cardiovascular-specific deaths (median 6.75 years follow-up). A log10 increase in ΣOH-PAHs was associated with higher all-cause mortality (HRadj = 1.39 [95%CI: 1.21, 1.61]), and possibly cancer-specific mortality (HRadj = 1.15 [95%CI: 0.79, 1.69]), and cardiovascular-specific mortality (HRadj = 1.49 [95%CI: 0.94, 2.33]). We observed substantial effect modification by age, smoking status, gender, and race/ethnicity across mortality endpoints. Risk of cardiovascular mortality was higher for non-Hispanic blacks and those in poverty, indicating potential disparities. Quantile g-computation joint associations for a simultaneous quartile increase in OH-PAHs were HRadj = 1.15 [95%CI: 1.02, 1.31], HRadj = 1.41 [95%CI: 1.05, 1.90], and HRadj = 0.98 [95%CI: 0.66, 1.47] for all-cause, cancer-specific, and cardiovascular-specific mortalities, respectively. DISCUSSION: Our results support a role for total PAH exposure in all-cause and cause-specific mortality in the U.S. population.

Association between environmental quality and prostate cancer stage at diagnosis.

BACKGROUND: Prostate cancer (PC) etiology is up to 57% heritable, with the remainder attributed to environmental exposures. There are limited studies regarding national level environmental exposures and PC aggressiveness, which was the focus of this study METHODS: SEER was queried to identify PC cases between 2010 and 2014. The environmental quality index (EQI) is a county-level metric for 2000-2005 combining data from 18 sources and reports an overall ambient environmental quality index, as well as 5 environmental quality sub-domains (air, water, land, built, and sociodemographic) with higher values representing lower environmental quality. PC stage at diagnosis was determined and, multivariable logistic regression models which adjusted for age at diagnosis (years) and self-reported race (White, Black, Other, Unknown) were used to test associations between quintiles of EQI scores and advanced PC stage at diagnosis. RESULTS: The study cohort included 252,164 PC cases, of which 92% were localized and 8% metastatic at diagnosis. In the adjusted regression models, overall environmental quality EQI (OR 1.20, CI 1.15-1.26), water EQI (OR: 1.34, CI: 1.27-1.40), land EQI (OR: 1.35, CI: 1.29-1.42) and sociodemographic EQI (OR: 1.29, CI: 1.23-1.35) were associated with metastatic PC at diagnosis. For these domains there was a dose response increase in the OR from the lowest to the highest quintiles of EQI. Black race was found to be an independent predictor of metastatic PC at diagnosis (OR: 1.36, CI: 1.30-1.42) and in stratified analysis by race; overall EQI was more strongly associated with metastatic PC in Black men (OR: 1.53, CI: 1.35-1.72) compared to White men (OR: 1.18, CI: 1.12-1.24). CONCLUSION(S): Lower environmental quality was associated with advanced stage PC at diagnosis. The water, land and sociodemographic domains showed the strongest associations. More work should be done to elucidate specific modifiable environmental factors associated with aggressive PC.

Pseudomeningocele and percutaneous intrathecal lead placement complication for spinal cord stimulator.

The incidence of symptomatic percutaneous intrathecal subarachnoid lead placement for spinal cord stimulator is almost an unheard of complication in the literature. We present the first case of a spinal cord stimulator implant with a complication of symptomatic intrathecal subarachnoid lead placement with a pseudomeningocele. This complication was found with myelogram and addressed by replacement with a new spinal cord stimulator implant with paddle leads instead of percutaneous leads and obliterating the pseudomeningocele tract. Technique for epidural lead placement is discussed. This case illustrates a spinal cord stimulator implant complication of intrathecal percutaneous lead placement with pseudomeningocele and its recognition and treatment involving replacement of the system while minimizing risk of postoperative cerebrospinal fluid leakage. Intraoperative neuromonitoring and interrogation of the spinal cord stimulator system during implantation are effective tools for accurate epidural lead placement.

Associations between environmental quality and infant mortality in the United States, 2000-2005.

BACKGROUND: The United States (U.S.) suffers from high infant mortality (IM) rates and there are significant racial/ethnic differences in these rates. Prior studies on the environment and infant mortality are generally limited to singular exposures. We utilize the Environmental Quality Index (EQI), a measure of cumulative environmental exposure (across air, water, land, sociodemographic, and land domains) for U.S. counties from 2000 to 2005, to investigate associations between ambient environment and IM across maternal race/ethnicity. METHODS: We linked 2000-2005 infant data from the U.S. Centers for Disease Control and Prevention to the EQI (n = 22,702,529; 144,741 deaths). We utilized multi-level regression to estimate associations between quartiles of county-level EQI and IM. We also considered associations between quartiles of county level domain specific indices with IM. We controlled for rural-urban status (RUCC1: urban, metropolitan; RUCC2: urban, non-metropolitan; RUCC3: less urbanized; RUCC4: thinly populated), maternal age, maternal education, marital status, infant sex, and stratified on race/ethnicity. Additionally, we estimated associations for linear combinations of environmental quality and rural-urban status. RESULTS: We found a mix of positive, negative, and null associations and our findings varied across domain and race/ethnicity. Poorer overall environmental quality was associated with decreased odds among Non-Hispanic whites (OR and 95% CI: EQIQ4 (ref. EQIQ1): 0.84[0.80,0.89]). For Non-Hispanic blacks and Hispanics, some increased odds were observed. Poorer air quality was monotonically associated with increased odds among Non-Hispanic whites (airQ4 (ref. airQ1): 1.05[0.99,1.11]) and blacks (airQ4 (ref. airQ1): 1.09 [0.9,1.31]). Rural status was associated with increased IM odds among Hispanics (RUCC4-Q4:1.36[1.04,1.78]; RUCC1-Q4: 1.04[0.92,1.16], ref. for both RUCC1-Q1). CONCLUSIONS: This study is the first to report on associations between ambient environmental quality and IM across the United States. It corroborates prior research suggesting an association between air pollution and IM and identifies residence in thinly populated (rural) areas as a potential risk factor towards IM amongst Hispanics. Some of the counterintuitive findings highlight the need for additional research into potentially differential drivers of environmental quality across the rural-urban continuum, especially with regards to the sociodemographic environment.

Intraneural Posterior Interosseous Nerve Lipoma with Complete Paralysis: Case Report and Review of the Literature.

An intraneural posterior interosseous nerve (PIN) lipoma is a rare entity consisting of two types and only two previously reported cases. Treatment involves total excision for the well-encapsulated "true intraneural lipomas" type and subtotal resection for the other type, fibrolipomatous hamartomas of the nerve. We present the management and surgical treatment of a case that illustrates a variation of the traditional posterolateral surgical approach for the complete excision of an intraneural PIN lipoma-contrary to the more commonly used anterior approach in literature-along with a literature review of intraneural PIN lipomas.

Associations between environmental quality and adult asthma prevalence in medical claims data.

As of 2014, approximately 7.4% of U.S. adults had current asthma. The etiology of asthma is complex, involving genetics, behavior, and environmental factors. To explore the association between cumulative environmental quality and asthma prevalence in U.S. adults, we linked the U.S. Environmental Protection Agency's Environmental Quality Index (EQI) to the MarketScan® Commercial Claims and Encounters Database. The EQI is a summary measure of five environmental domains (air, water, land, built, sociodemographic). We defined asthma as having at least 2 claims during the study period, 2003-2013. We used a Bayesian approach with non-informative priors, implementing mixed-effects regression modeling with a Poisson link function. Fixed effects variables were EQI, sex, race, and age. Random effects were counties. We modeled quintiles of the EQI comparing higher quintiles (worse quality) to lowest quintile (best quality) to estimate prevalence ratios (PR) and credible intervals (CIs). We estimated associations using the cumulative EQI and domain-specific EQIs; we assessed U.S. overall (non-stratified) as well as stratified by rural-urban continuum codes (RUCC) to assess rural/urban heterogeneity. Among the 71,577,118 U.S. adults with medical claims who could be geocoded to county of residence, 1,147,564 (1.6%) met the asthma definition. Worse environmental quality was associated with increased asthma prevalence using the non-RUCC-stratified cumulative EQI, comparing the worst to best EQI quintile (PR:1.27; 95% CI: 1.21, 1.34). Patterns varied among different EQI domains, as well as by rural/urban status. Poor environmental quality may increase asthma prevalence, but domain-specific drivers may operate differently depending on rural/urban status.

Endogenous Endophthalmitis in the American and Korean Population: An 8-year Retrospective Study.

PURPOSE: To study the clinical features of endogenous endophthalmitis (EE) in sample patient populations from the USA and South Korea over an 8-year period. METHODS: We reviewed data from 128 eyes of 60 American and 48 Korean patients diagnosed with EE and compared their clinical characteristics. RESULTS: Fungemia and liver abscess were the most common extraocular infection sources among American (26.7%) and Korean patients (33.3%), respectively. Klebsiella pneumoniae and Candida species were the most common pathogens of EE in the Korean and the American patients, respectively. Endophthalmitis caused by fungi had a better visual prognosis than that caused by bacteria (p = 0.001). Vitrectomy was beneficial for eyes with EE due to virulent bacteria presenting with worse than counting finger vision. CONCLUSIONS: The predisposing conditions and responsible organisms for EE vary in different regions of the world. The visual prognosis was strongly influenced by the underlying pathogen.

Computed tomography morphometric analysis of the central clival depression and petroclival angle for application of the presigmoid approach in the pediatric population.

AIMS: Lateral transtemporal approaches are useful for addressing lesions located ventral to the brainstem, especially when the pathologic diagnosis of the tumor dictates that a gross or near total resection improves outcomes. One approach, the presigmoid approach receives little attention in the pediatric population thus far. We sought to characterize morphometric changes, particularly the clival depth and the petroclival Cobb angle, that occur in the temporal bones of children and draw implications about doing a presigmoid approach in children. SETTINGS AND DESIGN: This study was a retrospective study performed at John Sealy Hospital, a level-one trauma center that takes care of pediatric injuries as well. SUBJECTS AND METHODS: We performed a morphometric analysis of noncontrast computed tomography head studies in 96 boys and 67 girls. Central clival depth and petroclival angle were obtained in the axial plane at the level of the internal auditory meatus using the method described by Abdel Aziz et al. STATISTICAL ANALYSIS USED: Descriptive statistics and Student's t-test to compare groups were calculated using Microsoft Excel. RESULTS: We found no gender difference in mean central clival depth or petroclival angle (P = 0.98 and P = 0.61, respectively). However, when we broke our cohort by age into those younger than 9 years of age and those 10 years or older, we found the petroclival angle decreased by 6.2° which was statistically significant (P < 0.000000006). CONCLUSIONS: These findings suggest that a presigmoid retrolabyrinthine approach is useful for children 9 years of age and younger as the petroclival angle appears to decrease resulting in a shallower clival depression in these patients.

Comparing Radiation Dose from Conventional Fluoroscopy to Intraoperative Cone Beam CT (O-arm) during Percutaneous Lesioning Procedures of the Gasserian Ganglion.

INTRODUCTION: The use of intraoperative CT-guidance during the percutaneous treatment of trigeminal neuralgia has become increasingly popular due to the greater ease of foramen ovale cannulation and decreased procedure times. Concerns regarding radiation dose to the patient, however, remain unaddressed. We sought to compare the emitted radiation dose from fluoroscopy with intraoperative CT for these procedures. METHODS: A retrospective review of percutaneous lesioning procedures for trigeminal neuralgia performed between 2010 until 2012 at our institution was conducted and radiation doses to the patient were recorded. We subsequently simulated four separate percutaneous trigeminal rhizotomies using the O-arm intraoperative CT (Medtronics, Minneapolis, MN, USA) to cannulate the foramen ovale bilaterally in two formalin-fixed cadaver heads. RESULTS: Seventeen successful percutaneous treatments for trigeminal neuralgia were performed during the study period. Eleven procedures containing complete records were included in the final analysis. For procedures using fluoroscopy, the mean dosage was 15.2 mGys (range: 1.15 - 47.95, 95% CI 7.34 - 22.99). Radiation dosage from the O-arm imaging system was 16.55 mGy for all four cases. An unequal variance t-test did not reach statistical significance (p=0.42). CONCLUSIONS: We did not observe a significant difference in radiation dose delivered to subjects when comparing CT-guided foramen ovale cannulation relative to fluoroscopy for percutaneous lesioning of the Gasserian ganglion. Additional study is required under operational settings.

Neurosurgical tactile discrimination training with haptic-based virtual reality simulation.

OBJECTIVE: To determine if a computer-based simulation with haptic technology can help surgical trainees improve tactile discrimination using surgical instruments. MATERIAL AND METHODS: Twenty junior medical students participated in the study and were randomized into two groups. Subjects in Group A participated in virtual simulation training using the ImmersiveTouch simulator (ImmersiveTouch, Inc., Chicago, IL, USA) that required differentiating the firmness of virtual spheres using tactile and kinesthetic sensation via haptic technology. Subjects in Group B did not undergo any training. With their visual fields obscured, subjects in both groups were then evaluated on their ability to use the suction and bipolar instruments to find six elastothane objects with areas ranging from 1.5 to 3.5 cm2 embedded in a urethane foam brain cavity model while relying on tactile and kinesthetic sensation only. RESULTS: A total of 73.3% of the subjects in Group A (simulation training) were able to find the brain cavity objects in comparison to 53.3% of the subjects in Group B (no training) (P  =  0.0183). There was a statistically significant difference in the total number of Group A subjects able to find smaller brain cavity objects (size ≤ 2.5 cm2) compared to that in Group B (72.5 vs. 40%, P  =  0.0032). On the other hand, no significant difference in the number of subjects able to detect larger objects (size ≧ 3 cm2) was found between Groups A and B (75 vs. 80%, P  =  0.7747). CONCLUSION: Virtual computer-based simulators with integrated haptic technology may improve tactile discrimination required for microsurgical technique.

Virtual reality spine surgery simulation: an empirical study of its usefulness.

OBJECTIVE: This study explores the usefulness of virtual simulation training for learning to place pedicle screws in the lumbar spine. METHODS: Twenty-six senior medical students anonymously participated and were randomized into two groups (A = no simulation; B = simulation). Both groups were given 15 minutes to place two pedicle screws in a sawbones model. Students in Group A underwent traditional visual/verbal instruction whereas students in Group B underwent training on pedicle screw placement in the ImmersiveTouch simulator. The students in both groups then placed two pedicle screws each in a lumbar sawbones models that underwent triplanar thin slice computerized tomography and subsequent analysis based on coronal entry point, axial and sagittal deviations, length error, and pedicle breach. The average number of errors per screw was calculated for each group. Semi-parametric regression analysis for clustered data was used with generalized estimating equations accommodating a negative binomial distribution to determine any statistical difference of significance. RESULTS: A total of 52 pedicle screws were analyzed. The reduction in the average number of errors per screw after a single session of simulation training was 53.7% (P  =  0.0067). The average number of errors per screw in the simulation group was 0.96 versus 2.08 in the non-simulation group. The simulation group outperformed the non-simulation group in all variables measured. The three most benefited measured variables were length error (86.7%), coronal error (71.4%), and pedicle breach (66.7%). CONCLUSIONS: Computer-based simulation appears to be a valuable teaching tool for non-experts in a highly technical procedural task such as pedicle screw placement that involves sequential learning, depth perception, and understanding triplanar anatomy.

A novel virtual reality simulation for hemostasis in a brain surgical cavity: perceived utility for visuomotor skills in current and aspiring neurosurgery residents.

OBJECTIVE: To understand the perceived utility of a novel simulator to improve operative skill, eye-hand coordination, and depth perception. METHODS: We used the ImmersiveTouch simulation platform (ImmersiveTouch, Inc., Chicago, Illinois, USA) in two U.S. Accreditation Council for Graduate Medical Education-accredited neurosurgical training programs: the University of Chicago and the University of Texas Medical Branch. A total of 54 trainees participated in the study, which consisted of 14 residents (group A), 20 senior medical students who were neurosurgery candidates (group B), and 20 junior medical students (group C). The participants performed a simulation task that established bipolar hemostasis in a virtual brain cavity and provided qualitative feedback regarding perceived benefits in eye-hand coordination, depth perception, and potential to assist in improving operating skills. RESULTS: The perceived ability of the simulator to positively influence skills judged by the three groups: group A, residents; group B, senior medical students; and group C, junior medical students was, respectively, 86%, 100%, and 100% for eye-hand coordination; 86%, 100%, and 95% for depth perception; and 79%, 100%, and 100% for surgical skills in the operating room. From all groups, 96.2% found the simulation somewhat or very useful to improve eye-hand coordination, and 94% considered it beneficial to improve depth perception and operating room skills. CONCLUSION: This simulation module may be suitable for resident training, as well as for the development of career interest and skill acquisition; however, validation for this type of simulation needs to be further developed.

Neurosurgery simulation in residency training: feasibility, cost, and educational benefit.

BACKGROUND: The effort required to introduce simulation in neurosurgery academic programs and the benefits perceived by residents have not been systematically assessed. OBJECTIVE: To create a neurosurgery simulation curriculum encompassing basic and advanced skills, cadaveric dissection, cranial and spine surgery simulation, and endovascular and computerized haptic training. METHODS: A curriculum with 68 core exercises per academic year was distributed in individualized sets of 30 simulations to 6 neurosurgery residents. The total number of procedures completed during the academic year was set to 180. The curriculum includes 79 simulations with physical models, 57 cadaver dissections, and 44 haptic/computerized sessions. Likert-type evaluations regarding self-perceived performance were completed after each exercise. Subject identification was blinded to junior (postgraduate years 1-3) or senior resident (postgraduate years 4-6). Wilcoxon rank testing was used to detect differences within and between groups. RESULTS: One hundred eighty procedures and surveys were analyzed. Junior residents reported proficiency improvements in 82% of simulations performed (P < .001). Senior residents reported improvement in 42.5% of simulations (P < .001). Cadaver simulations accrued the highest reported benefit (71.5%; P < .001), followed by physical simulators (63.8%; P < .001) and haptic/computerized (59.1; P < .001). Initial cost is $341,978.00, with $27,876.36 for annual operational expenses. CONCLUSION: The systematic implementation of a simulation curriculum in a neurosurgery training program is feasible, is favorably regarded, and has a positive impact on trainees of all levels, particularly in junior years. All simulation forms, cadaver, physical, and haptic/computerized, have a role in different stages of learning and should be considered in the development of an educational simulation program.